This is one of the theatrically released BSG films. It's basically The Living Legend 1&2 and 20 minutes worth of Fire In Space cut into a 1 hour 45 minute feature film. It works surprisingly well, the Fire in Space footage was clearly added to give extra jeopardy at the end with Adama in trouble and the guys having to put out the fire. It moves along at an exciting pace and there's plenty of action, but the only shame is that some of the character moments between Sheba and Starbuck and Apollo winds up on the cutting room floor, along with a couple of subplots. That said it was still enjoyable to see these episodes as a 'movie' as it were.There's also some exclusive effects footage that can only be seen here and was never in the episodes.
If you're a casual viewer looking for a bit of nostalgia without wanting to buy the complete series, or if you're looking to follow up the first 'film' version then this is a perfect buy. I already own the complete series but being a fan I bought this as well, and I wasn't disappointed.